Tooth arrangement for screw type comminuting devices



Oct. 20,- 1953 c. BURNER 6,122

TOOTH ARRANGEMENT FOR SCREW TYEE' CQM INUTING DEVICES Filed June 24. 1952 w Q r L A IN V EN TOR.

Patented Oct. 20, 1953 ARRANGEMENT FOR SCREW TYPE COMMINUTING DEVICES 'roorn OFFICE I Christian Biirneig obernburg (Main), Germany,

assignor to Vereinigte Glanzstofi-Fabriken A. G., Wuppertal-Elberfeld, Germany Application June 24, 1952, Serial No. 295,205

v In Germany June 25, 1951 v 1 The present invention relates to comminuting devices. More particularly, the present invention relates to toothed members which are adapted to be mounted in'screw type'comminuting devices.

It has been found that screw type comminuting devices which are provided with toothed members to aid in the comminuting process do not generally provide the best possible results because the teeth within these devices are of 7 Claims. (01. 241 -255) a uniform size and do not provide a product having particles of the desired fineness.

1 located within this. cylindrical casing, extends along the length thereof, and is mountecl'on the end walls of the casing for rotation about the axis of the latter. A plurality of pairs of opposite wall portions are fixed to the screw member between convolutions thereof to form separate chambers with said convolutions, the wall members on each side of said axis terminating in edge portions located along a straight line substantially at the outer periphery of said screw member and extending across the convolutions thereof in a direction parallel to the axis of said casing. A pair of elongated strips are fixed to the screw member and respectively extend along these lines, these strips each having a plurality of teeth formed along a free outer elongated edge thereof and gradually diminishing in sizein'a direction extending from the inlet to the outlet end of the casing. These elongated strips may have end portions adjacent to the inlet end of the casing provided with straight cutting edges.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and itsimethod' of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connec- I tion with the accompanying drawings, in which; Fig. 1 is a perspective, side sectional view of one possible apparatus for carrying out the present invention; and

Fig. 2 is aside view of a toothed strip constructed in accordance with the present invention.

Referring now to the drawings and more particularly to Figure 1, there is shown a cylindrical casing I having an inner surface provided with pyramidal teeth 2 and inlet and outlet ends respectively located at the right and left end portions of the casing, as viewed in Figure 1. On opposite end Walls of the casing there is rotatably mounted, for-turning movement about the axis of the casing,'a screw 3-having fixedly connected thereto oppositewall portions 5 which form separate chambers with the convolutions of the screw 3, the first of these chambers being indicated-by numerall. Thesewalls 5, on each side of the casing axis, havefree outer edges located along a straight line; and a pair of toothed members '4 are fixedto the worm 3 and extend along these straight lines, these toothed members 4 being spaced from the pyramidal teeth 2 on the inner surface of easing! by a gap 6. c a r As is shownmost clearly in Figure 2, each of toothed. strips 4 is provided-with 'teethwhich gradually diminish in size in a direction extending from the inlet to the outlet end of the casing l. Also the toothed strips 4 are provided with straight cutting edges 8 at the end portions thereof adjacent to the inlet end of the casing i. The above described apparatus operates as follows:

Material to be comminuted is supplied to the interior of easing I through the inlet thereof and enters the first chamber I and then moves toward the outlet end of the casing, successively entering the several chambers formed by the 'convolutions ofthe screw .3 and the walls 5. As .the material moves toward the outlet end of the emerging from the outlet of casing I is very finely,

divided. V 7

It will be understood that each of the elements described above,or two or more together, may also find a useful application in other types of screw type comminuting devices differing from the typesdescribed above.

While I have illustrated and described the in vention as embodied in screw type comminuting devices adapted to very finely divide the material being comminuted, I do not intend to be limited to the details shown, since various modifications and structural changes may be made without departing any way from the spirit of :my invention.

Without further analysis, the foregoing will so fully reveal the gist of my invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art. fairly constitute essential characteristics of the generic or specific aspects of this invention an therefore, such adaptations should and are intended to be comprehended within thameaning and range of equivalence of the following claims.

What I claim as new and desire to secure by Letters Patent is:

1. A screw type comminuting apparatus comprising, in combination, a cylindrical casing having an inlet end and an outlet end; a screw located within said cylindrical casing, extending along the axis thereof, and being mounted on said cylindrical. casing for rotation about said axis; and an elongated toothed strip fixedly connected torsaid screw at the outer surface thereof and extending in a direction substantially parallel to said axis, saidstrip being. provided with-a plurality of teeth wliichtare ofailarger size atla portion of said strip adjacent to said inletend of said casing thanzata portion of said strip'adiacent to said outlet end of said casing.

2. Ascrew typecomminiiting apparatus as defined in claimland. wherein .asecond strip identical with saidfifirstmentioned strip is located op- -posite the, latter on saidzscrew member.

3. vA screw type.comminuting apparatus as'defined inclaim 1 and, wherein the teeth of said stripgr-adualhr diminisninsize inza direction-ex, tending fromathe inlet ,endtof saidcasing tothe outlet end thereof.

4. A screw' type comminuting-apparatus ,as defined in claim -3 and-wherein saida stript is provided 4 with a straight cutting edge at the end portion thereof adjacent to the inlet end of said casing.

5. A screw type comminuting apparatus as defined in claim 1 and wherein said strip is provided with a straight cutting edge at the ,end portion thereof adjacent to the inlet end of said casing.

6. A screw type comminuting apparatus comprising, in combination, a cylindrical casing having an inner toothed surface, an inlet end and anloutletendmnd a pair of opposite end walls; a screw member located within said cylindrical casing, extending along the length thereof, and being mounted. on said end walls for rotation about the axis 10f said cylindrical casing; a plurality of pairs of opposite wall portions fixed to said screw member between convolutions thereof to form separate chambers with said convolutions, the wall members on each side of said axis terminating in edge portions located along ,a straight line substantially at the outer periphery of said screw member and extending across the convolutions thereof in a direction parallel to said axis; and a pair of elongated strips fixed to said screw'member and respectively extendingalong saidlines; said-strips each having aplurality of teethformed along a free outer elongated edge thereof, and said teeth gradually diminishing in sizein a direction extending'from the inlet to the outlet end of said casing.

7. Apparatus as defined in claim 6. and wherein each of said strips is provided with a straight cutting edge at the end portion thereof located adjacent to the inlet end ofsaid casing.

CHRISTIANIBfiRNER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2;47-6335- Tusson July 19, 1949 FOREIGN PATENTS Number Country Date 443,481 "GreatBnitain Feb. 28, I936 

